objective-c - 可达性类(class)在iOS中不起作用

我已经实现了可达性Api 2.2。当网络从关闭状态变为开启状态时，它不会触发。

另外，我可以在应用程序委托中实现它吗？如果是这样，我应该在哪里删除观察者？

这是我的代码(不调用解雇模型viewController)

- (void)viewDidLoad
{
    // check for internet connection
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(checkNetworkStatus:) name:kReachabilityChangedNotification object:nil];

     internetReachable = [[Reachability reachabilityForInternetConnection] retain] ;
    [internetReachable startNotifier];
    // check if a pathway to a random host exists
    hostReachable = [[Reachability reachabilityWithHostName: @"www.google.com"] retain];
    [hostReachable startNotifier];
 }

- (void) checkNetworkStatus:(NSNotification *)notice
{
    // called after network status changes

    NetworkStatus hoststatus=[hostReachable currentReachabilityStatus];

    NetworkStatus internetStatus=[internetReachable currentReachabilityStatus];

    for (NSString *msg  in messageArray) {
        [stringg appendString:[NSString stringWithFormat:@"%@",msg]];
    }

    if  (hoststatus==NotReachable||internetStatus==NotReachable) {
        [self.navigationController presentModalViewController:inter animated:YES];
    }
    else{
        [self dismissModalViewControllerAnimated:YES];
    }

    [inter release];
}



- (void)viewDidUnload
{

    [[NSNotificationCenter defaultCenter] removeObserver:self];
    [super viewDidUnload];
}

最佳答案

您在哪里注册通知？

您需要这样的东西:

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(reachabilityChange:)
                                             name:kReachabilityChangedNotification
                                           object:nil];

我使用作为参数传递的可达性对象，如下所示:

- (void) reachabilityChange: (NSNotification*) notification
{
    Reachability* curReach = [notification object];
    NSParameterAssert([curReach isKindOfClass: [Reachability class]]);
    BOOL isServerCurrentlyReachable = (NotReachable != [curReach currentReachabilityStatus]);
    BOOL wasServerPreviouslyReachable = self.isServerReachable;
    self.isServerReachable = isServerCurrentlyReachable;

    if (NO == wasServerPreviouslyReachable && YES == isServerCurrentlyReachable)
    {
        // Moving from non reachable to reachable state

    }
    else if (YES == wasServerPreviouslyReachable && NO == isServerCurrentlyReachable)
    {
        // Moving from a reachable to a non reachable state

    }
}

您似乎没有使用它。

同样，通知也可以多次以相同的状态被调用，因此您需要确保将其考虑在内，如代码段所示。

如果您在应用程序委托中使用它，则停止/删除applicationDidResignActive中的内容似乎是合适的地方。

关于objective-c - 可达性类(class)在iOS中不起作用，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/10790081/